Blasting cartridge



Dec. l, 1936. F; 1| KNEELAND 2,062,912

` BLASTING CARTRIDGE Filed May 1, 1955 Patented Dec. 1, 1936 UNITED STATES BLASTING CARTRIDGE Frank H. Kneeland, Elmhurst, Ill., asslgnor to Safety Mining Company, Chicago, lli., a corporation Application May l, 1933, .Serial No. 668,869

20 Claims. (C1. 1027) This invention relates to improved method and f apparatus for the blasting of coal by means of compressed air or other gas.

The principal object of the invention is to im- 5 prove the discharge mechanism of such a blasting device.

Referring to the drawing, the single gure is a view in longitudinal section through a complete cartridge of the type under consideration and 10 embodying a preferred form of the present invention. t

In the method of blasting under consideration, compressed air or other gases may be introduced into a reusable cartridge or container at what may 15 be termed the working pressure. By this is meant pressures at which the charge of compressed air or other gas will be capable of performing useful work when liberated.

The particular construction shown consists of 20 a tubular cartridge I having end caps 2 and 3 and a closure disc 4 designed to seal the discharge opening of the cartridge. Both the caps 2 and 3 have sealing engagement with the cartridge I so t as to conne the charge of compressed air until 25 such time as release thereof is desired. The charge of compressed air or other gas may be introduced into the cartridge by means of a valve Il and charging ports I provided in the cap member 2.

30 The pressures contemplated for coal mining and work of a similar nature range from 6,000 to 10,000 pounds per square inch. The disc 4 is so designed as to be incapable of sustaining or supporting pressures of this magnitude, and it is therefore necessary to provide an auxiliary support for the disc to prevent rupturing thereof until discharge is desired. In the present instance this auxiliary support takes the form of a tubular post which may be made of cast iron or any 40 readily destructible or shatterable material having reasonably high compressive strength values. 'I'his post 5 seats at one end on the internal end wall of the discharge cap 3 and at its other end has a slightly broadened base for supporting engagement with the disc 4. Thus, it will be seen that by destroying the post 5 the reinforcement of disc 4 is removed and this disc will promptly fail under the influence of the high pressure charge contained within the cartridge, the discharge 5 gases then passing outwardly through the several radial ports 8 of the discharge cap 3, and into the surrounding material to be broken down.

By way of illustrating one practical method of removing the reinforcement of the disc 4, there 55 has been shown a detonator 6 positioned within a bore provided in post 5 with the usual current carrying wires 1 extending out through the end of the discharge cap 3 for connection to an ordinary ring cable. Upon the application of current 6 to the wires l the detonator is discharged, resulting in a rather complete shattering of the post 5. Thisis immediately followed by rupture of the disc 4, thus liberating the normally conned charge of gas. It will be understood that the disc 4 may be made of metal, bre or other suitable 5 material.

Thus, there is provided an entirely practical and reliable means for suddenly liberating a confined charge of gas at working pressure. It should be understood, however, that the principles in- 10 volved herein may be practiced by a variety of devices diiering in physical form from that herein shown.

I claim:

1. A material breaking device comprising a reusable steel cartridge having a chamber designed to receive a quantity of gas at working pressure,

a closure element associated with said cartridge for normally conning the charge of gas but being incapable in itself of withstanding the pressure of said charge, a shatterable member of less structural strength than said cartridge for normally providing support for said closure element, thereby enabling it to withstand said pressure, and means distinct from the pressure in said chamber for causing shattering of said member.

2. A reusable blasting cartridge having a discharge opening in combination with a closure element for the discharge opening of said cartridge, which closure element is of insufficient strength in itself to withstand the pressure of the charge employed within the cartridge, an element destructible by a force less than that which would destroy said cartridge, designed to support said closure element and electrical means for causing destruction of said destructible element.

3. A blasting cartridge comprising a steel body having a gas chamber therein and a discharge opening leading to the exterior of said cartridge, a rupturable closure member for said discharge opening, means for supporting said closure member to prevent rupture thereof, and means in addition to the charge in said chamber for rupturing said supporting means to permit the closure member to rupture under the influence of the pressure of a charge of compressed gas contained within said cartridge.

4. A blasting cartridge having a discharge opening, a rupturable disc for normally closing said opening, a supporting member having engagement with said disc for normally preventing the rupture thereof and a detonator for destroying said supporting member.

5. A material blasting device comprising a container capable of holding a charge of compressed gas at work performing pressure and having a discharge opening, closure means for said opening capable of holding a charge of desired pressure against liberation through said opening.

and means in addition to the pressure of the charge in said container and havingembodied therein a detonator for causing failure of 'said' closure means to effect liberation of a charge.

6. A material blasting device comprising a contalner capable of holding a charge of compressed gas atwork performing pressure and having a discharge opening, closure means for said openingcapable of holding a charge of desired pressure against liberation through said opening, and electrically actuated v means in adition to the pressure of the blasting charge andeiective independently of such pressure and associated with said closure means for causing destruction of the entire closure means to eect liberation of a charge.

7, A material blasting device comprising a container capable of holding a charge of compressed gas at work performing pressurev and having a discharge opening, closure meansfor said opening capable of holding a charge of desired presmeans housed within said closure means and operable at-will for generating a force to cause failure of the latterto effect liberation of a charge. l

8. A,material1blasting'ldevice comprising a container capable of holding a charge of scompressed gas atwork performing pressure and having a discharge opening, means for normally preventing liberation of a charge through said opening and including a destructible post, and means in addition to the pressure conditions in said container for destroying said post to effect liberation of a charge. y

. 9. A material blasting devicecomprising a container capable of holdingra charge of compressed gas at Work performing pressure and having a discharge opening, means for normally preventing liberation of a charge through said opening and including a destructible element, and electrical means supplemental to the pressure of the charge in said-container and effective independently of such pressure for destroying said element to effect liberation of a charge.

10. A material blasting device comprising a container capable of holding a charge of com-v pressed gas at Work performing pressure and having a discharge opening, means for normally preventing liberation of a charge through said opoening and including a destructible element, and a `fdetonator for creating a fracturing pressure supplemental to the pressure of the blasting charge but effective independently of such pressure for destroying said element to effect liberation of a charge. l

f y v11. A material blasting device comprising a controlled means embodied in the cartridge and operative on`current supply thereto for effecting removal of said element from supporting engagement with said disc to permit failure of the latter. 12. A material blasting device comprising a container capable of holding a charge of compressed gas at work performing pressure and having a discharge opening, a rupturable disc for closing said opening, a destructible post engaging ,accaniti release means for the blasting charge and including closure means of insufficient strength to withstand the pressure of the blasting charge Withinthe container, destructible means designed to support/.said closure means, and electrical means Wholly outside said chamber for causing destruction of saiddestructible means.

14. In a blasting cartridge, a container for receiving a blasting charge, rupturable release means for the blasting charge comprising a rupturable disc, rupturable supporting means having engagement with said disc for normally preventing the rupture thereof, and means embodied in the cartridge for creating an explosion for imparting a rupturing pressure, distinct from the pressure of the blasting charge, to the supporting means for rupturing the latter.

15. In a blasting cartridge, a container for receiving a blasting charge, release means for the blasting charge, means for maintaining said release means closed, and means embodied in said latter means for creating an explosion to render said maintaining means ineffective, thereby to release suddenly the blasting charge.

16. In a blasting cartridge, a container for receiving a blasting charge, release means for said blasting pressure, destructible means for maintaining said release means closed, and means embodied in said destructible means for causing an explosive effect to destroy said destructible means, thereby to release the blasting charge.

17. In a blasting cartridge, a container for receiving a blasting charge, release means for said blasting charge, a hollow destructible strut for maintaining said release means closed, and an explosive Within said strut for destroying the latter, thereby suddenly to release the blasting charge.

18. In a blasting cartridge, a container for receiving a blasting charge, shatterable release means for said blasting charge, and self-contained means embodied wholly within the cartridge for imparting a shattering pressure, distinct from and acting independently of the pressure of the blasting charge in said container, to said release means to destroy the latter, thereby to release suddenly the blasting charge.

19. A material blasting device comprising a container providing a chamber capable of holding a charge of compressed gas at work performing pressure and having a discharge opening, means for normally preventing liberation of the charge through said opening including a destructible hollow post, and means positioned wholly within said post for destroying said post to ei'ect liberation of the charge.

20. In a blastingcartridge, a container for receiving a blasting charge, release means for the blasting charge and including closure means of insufficient strength to withstand the pressure charge Within the container, destructible means designed to support said closure means, and electrical means acting directly on said destructible means for causing destruction of the latter, to effect charge release.

FRANK I-I. KNEELAND. 

